The present invention relates to a filling apparatus for the filling of refillable aerosol packages, as defined in the claims.
From international patent application WO 92/12912, a refillable aerosol package is known which consists of a pressure resistant cylindrical shell and an elastic or flexible container deformable by pressure, sealed against the edges of an aperture in the cover of the shell by means of a plug provided with a push valve as used in aerosol packages. The elastic or flexible container divides the interior of the aerosol package into two spaces hermetically sealed from each other, the space inside the flexible container being filled with a liquid of a suitable viscosity while the space between the container and the shell of the package is filled with a propellant gas.
Such an aerosol package is very favorable in respect of environmental protection as it does not release any emissions into the environment and the package can be reused hundreds of times, so it can be said that a package once bought is everlasting. The only problem with the package is its refilling. At present, containers are refilled using compressed air by pumping them full, but this is a slow and inaccurate filling method because measuring the volume of liquid pumped into the package or the pressure in the package with sufficient accuracy during the filling operation is difficult.